Epidemiology and prevention of bladder cancer

Risk factors for bladder cancer

AIMS AND BACKGROUND

To summarize risk factors for bladder cancer, emphasizing the role of recently established associations and to present some ongoing debates on the issue.

METHODS

A systematic literature search was performed using MEDLINE database on bladder cancer risk factors between January 1985 and June 2006 and by detailed examination of the references of original articles, reviews and monographs retrieved.

RESULTS

Cigarette smoking is recognized as the main cause of bladder cancer and accounts for about 50% of cases in developed countries. A strong link exists between the amount and duration of cigarette smoking. A high risk of bladder carcinoma has been observed in workers exposed to some aromatic amines. Based on these and other occupational risks, it has been estimated that 5-10% of bladder carcinomas in industrialized countries were due to exposures of occupational origin. Infectious agents have a major influence on bladder cancer risks in the areas of the world where Schistosoma haematobium infestation is endemic. Other potential risk factors for bladder cancer are other urinary tract infections and drinking tap water with chlorination by-products or arsenic. Exposure to certain drugs, like cyclophosphamide used in chemotherapy and heavy consumption of phenacetin-containing analgesics, has been shown to cause bladder cancer in humans. Total fluid intake and high consumption of fruits and vegetables are probably associated with a small decrease in risk.

CONCLUSIONS

Avoidance of tobacco smoking and incriminated occupational exposures, habitual intake of fresh fruits and vegetables, and prevention and control of urinary tract infections should be recommended for bladder cancer prevention. Further studies are required to assess the role of genetic polymorphisms and their modifying effect of lifestyle risk factors for bladder cancer occurrence and to evaluate the benefit of bladder cancer screening, particularly in those at high risk.

Urine telomerase activity for the detection of bladder cancer in females

PURPOSE

Previous studies have shown that telomerase activity in bladder washings and voided urine represents an important noninvasive tool for bladder cancer diagnosis. With the present case-control study conducted on 212 women, including 144 healthy individuals and 68 patients, at first diagnosis of bladder cancer we confirmed previously obtained diagnostic results and improved the accuracy of this diagnostic assay.

MATERIALS AND METHODS

Telomerase activity was evaluated by quantitative telomeric repeat amplification protocol assay and expressed as arbitrary enzymatic units.

RESULTS

At the best overall cutoff of 50 arbitrary enzymatic units sensitivity was 87% and specificity was 66%. A breakdown analysis as a function of age showed a higher assay accuracy in women younger than 75 years (sensitivity 91% and specificity 69%) compared to older women (sensitivity 64% and specificity 59%).

CONCLUSIONS

Other reasons in addition to age may account for the lower specificity in women with respect to men. In particular, a high number of telomerase positive nonurothelial cells in urine from females could be responsible for false-positive telomeric repeat amplification protocol results. Urine telomerase activity detected by telomeric repeat amplification protocol appears to be a good diagnostic tool in females although it is more accurate in younger than in older women.

Inducible Nitric Oxide Synthase Promoter Polymorphism, Cigarette Smoking, and Urothelial Carcinoma Risk

OBJECTIVES

Bladder carcinoma has a high inducible nitric oxide synthase (iNOS) content, and a highly polymorphic (CCTTT)n repeat in the iNOS promoter region has been identified. We explored whether this iNOS promoter polymorphism and cigarette smoking are associated with urothelial carcinoma (UC) risk.

METHODS

A total of 250 patients with pathologically confirmed UC and 250 unrelated noncancer controls were serially recruited at the Chia Yi Christian Hospital from August 2002 to May 2005. Multivariate logistic regression analysis was used to calculate the odds ratio and 95% confidence interval (CI).

RESULTS

A significantly increased UC risk was found in those who had smoked more than 30 years (odds ratio 2.4, 95% CI 1.5 to 4.2). The study subjects carrying the 12-repeat allele had a significantly increased UC risk (odds ratio 1.7, 95% CI 1.1 to 2.5). We also found the investigated polymorphism was related to clinical stage (P = 0.043). Of those who had ever smoked, those with the short/long (S/L) and long/long (L/L) genotypes (S, 9 to 11 repeats; L, 12 to 18 repeats) and the 12-repeat allele had a significantly increased UC risk of 3.5 (95% CI 1.7 to 7.3) and 4.5 (95% CI 2.2 to 8.9), respectively. Of the study subjects who had smoked longer than 30 years, those with S/L and L/L genotypes and the 12-repeat allele had significantly increased UC risks of 2.4 (95% CI 1.3 to 4.7) and 3.8 (95% CI 1.8 to 8.0), respectively.

CONCLUSIONS

These findings suggest that the polymorphic (CCTTT)n repeat in the iNOS promoter region might be involved in the development of UC, especially in those who have ever smoked.

Occupational exposure of hairdressers to [14C]-para-phenylenediamine-containing oxidative hair dyes: A mass balance study

We monitored the exposure of hairdressers to oxidative hair dyes for 6 working days under controlled conditions. Eighteen professional hairdressers (3/day) coloured hairdresser's training heads bearing natural human hair (hair length: approximately 30 cm) for 6 h/working day with a dark-shade oxidative hair dye containing 2% [14C]-para-phenylenediamine (PPD). Three separate phases of hair dyeing were monitored: (A) dye preparation/hair dyeing, (B) rinsing/shampooing/conditioning and (C) cutting/drying/styling. Ambient air and personal monitoring samples (vapours and particles), nasal and hand rinses were collected during all study phases. Urine (pre-exposure, quantitative samples for the 0-12, 12-24, 24-48 h periods after start of exposure) and blood samples (blank, 4, 8 or 24 h) were collected from all exposed subjects. Radioactivity was determined in all biological samples and study materials, tools and washing liquids, and a [14C]-mass balance was performed daily. No adverse events were noted during the study. Waste, equipment, gloves and coveralls contained 0.41+/-0.16%, dye mixing bowls 2.88+/-0.54%, hair wash 45.47+/-2.95%, hair+scalp 53.46+/-4.06% of the applied radioactivity, respectively. Plasma levels were below the limit of quantification (10 ng PPDeq/mL). Total urinary 0-48 h excretion of [14C] levels ranged from a total of <2-18 microg PPDeq and was similar in subjects exposed during the different phases of hair dyeing. Minimal air levels at or slightly above the limit of quantification were found in a few personal air monitoring samples during the phases of hair dyeing and hair cutting, but not during the rinsing phase. Air area monitoring samples or nasal rinses contained no measurable radioactivity. Hand residues ranged from 0.006 to 0.15 microg PPDeq/cm2, and were found predominantly after the cutting/drying phase. The mean mass balance of [14C] across the six study days was 102.50+/-2.20%. Overall, the mean, total systemic exposure of hairdressers to oxidative hair dyes during a working day including 6 hair dyeing processes was estimated to be <0.36 microg PPDeq/kg body weight/working day. Our results suggest that (a) current safety precautions for the handling of hair dyes offer sufficient protection against local and systemic exposure and (b) professional exposure to oxidative hair dyes does not pose a risk to human health.

Mechanisms of disease: The epidemiology of bladder cancer

Mortality from bladder cancer has shown downward trends over the last 2 decades in several western European countries (albeit 10-15 years later than similar trends in the US), but is still increasing in some eastern European countries. Tobacco smoking and occupational exposure to aromatic amines are the two major established environmental risk factors for bladder cancer. Controlling exposure to these factors has been an important contributor to the reduction in bladder cancer mortality, particularly among men. Diet could influence bladder carcinogenesis, as many compounds contained in foods--and their metabolites--are excreted through the urinary tract. Fruit and vegetable consumption was inversely related with bladder cancer in many studies, but no consistent association has emerged between intake of related micronutrients and reduced risk of bladder cancer. Other widely investigated lifestyle habits are probably not associated with risk of developing bladder cancer (e.g. coffee consumption, artificial sweetener use, hair dyes) or are difficult to assess (e.g. fluid intake). Infections and stones in the urinary tract might cause chronic irritation of the bladder epithelium, and thus increase bladder cancer risk. First-degree relatives of bladder cancer patients have a 50-100% increased relative risk of developing the disease, a risk that could be even higher when the proband is diagnosed at an early age.

An Updated Review of the Literature: Risk Factors for Bladder Cancer with Focus on Occupational Exposures

Workplace exposures account for 5 to 25% of all bladder cancer cases. A critical review of the literature between 1938 and 2004 was performed, with a focus on occupational exposures. Occupational exposure to bladder carcinogens, particularly to beta-naphthylamine occur in a number of industries, including aromatic amine manufacture, rubber and cable manufacture, and dyestuff manufacture and use. Risks to workers in a number of new occupations and industries are reviewed. Nonoccupational risk factors that are known or at one time have been thought to increase the risk of bladder cancer are also discussed.

Chemopreventive property of dietary ginger in rat urinary bladder chemical carcinogenesis

The modifying potential of ginger on the development of preneoplasia and tumors in the male Wistar rat urinary bladder was investigated in a 36-week-long initiation-promotion assay for chemical carcinogenesis. Groups G1 to G3 were given 0.05% N-butyl-N-(4-hydroxybutyl)-nitrosamine (BBN) in drinking water for 5 weeks and a 3% uracil meal for the subsequent 3 weeks. Groups G4 and G5 were treated with 3% uracil only for the same period. After these steps, groups G2, and G3 and G4 were fed for 26 weeks a ginger extract mixed at 0.5 and 1.0% in a basal diet, respectively. Thirty six weeks after the beginning of the experiment all rats were killed. The multiplicity of urothelial lesions (hyperplasia and neoplasia) was significantly lower (P = 0.013) in group G3 than in groups G1 and G2. The results suggest that 1.0% ginger meal exerts a protective effect on the post-initiation stage of rat chemically-induced urothelial carcinogenesis.

Effects of ginger (Zingiber officinale Roscoe) on DNA damage and development of urothelial tumors in a mouse bladder carcinogenesis model

Extracts of the spice ginger (Zingiber officinale Roscoe) are rich in gingerols and shogaols, which exhibit antioxidant, anti-inflammatory, antifungal, antimycobacterial, and anticarcinogenic proprieties. The present study evaluated the chemoprotective effects of a ginger extract on the DNA damage and the development of bladder cancer induced by N-butyl-N-(4-hydroxibutyl) nitrosamine (BBN)/N-methyl-N-nitrosourea (MNU) in male Swiss mice. Groups G1-G3 were given 0.05% BBN in drinking water for 18 weeks and four i.p. injections of 30 mg/kg body weight MNU at 1, 3, 10, and 18 weeks. Group G4 and G5 received only the BBN or MNU treatments, respectively, and groups G6 and G7 were not treated with BBN or MNU. Additionally, Groups G2, G3, and G6 were fed diets containing 1, 2, and 2% ginger extract, respectively, while Groups G1, G4, G5, and G7 were fed basal diet. Samples of peripheral blood were collected during the experiment for genotoxicity analysis; blood collected 4 hr after each MNU dose was used for the analysis of DNA damage with the Comet assay (assay performed on leukocytes from all groups), while reticulocytes collected 24 hr after the last MNU treatment of Groups G5-G7 were used for the micronucleus assay. At the end of the experiment, the urinary bladder was removed, fixed, and prepared for histopathological, cell proliferation, and apoptosis evaluations. Ginger by itself was not genotoxic, and it did not alter the DNA damage levels induced by the BBN/MNU treatment during the course of the exposure. The incidence and multiplicity of simple and nodular hyperplasia and transitional cell carcinoma (TCC) were increased by the BBN/MNU treatment, but dietary ginger had no significant effect on these responses. However, in Group G2 (BBN/MNU/2% ginger-treated group), there was an increased incidence of Grade 2 TCC. The results suggest that ginger extract does not inhibit the development of BBN-induced mouse bladder tumors.

Use of selenium in chemoprevention of bladder cancer

The anticarcinogenic potential of selenium was first identified nearly 40 years ago in geographical studies that reported lower death rates for cancer in regions with high levels of selenium. Cancer of the bladder was one of the body sites found to share this inverse association. Although many subsequent studies have been done on selenium and cancer, only a few have specifically assessed the relation with bladder cancer. However, the high recurrence rate and ability to monitor bladder urothelial-cell carcinoma make selenium a good candidate for chemoprevention. Evidence suggests that selenium is a biologically plausible, safe, and efficacious potential chemoprevention agent for bladder cancer. Large tertiary chemoprevention trials are needed to further investigate the role of selenium in the prevention of bladder cancer. Future studies should assess the best dose and form of selenium, and whether the protective effect of selenium differs between the sexes.

Case-control analysis of dietary folate and risk of bladder cancer

Dietary folate, a water-soluble B vitamin found in a variety of fruits and vegetables, is of particular interest as a chemopreventive agent due to its role in DNA methylation and DNA synthesis and repair. We hypothesized that individuals with low folate intake would be at an increased risk for bladder cancer. Using an ongoing case-control study we assessed dietary folate in 409 incident bladder cancer patients and 451 healthy control subjects. A food-frequency questionnaire was used to estimate naturally occurring food folate (microg/kcal/day), dietary folate equivalents (DFE) from food sources (microg DFE/kcal/day), and DFE from all sources (microg DFE/kcal/day). Unconditional logistic regression analyses were used to estimate odds ratios (ORs) and 95% confidence intervals (CIs). Bladder cancer patients reported a statistically significant lower intake of folate than control subjects for food folate and DFE from food sources (P < 0.001) but not for DFE from all sources (P = 0.061). In the highest quartile of food folate intake there was a 54% reduced risk for bladder cancer (OR = 0.46; 95% CI = 0.29-0.73) after adjusting for age, gender, ethnicity, smoking, and total energy intake. Similarly, the highest quartile of intake was associated with a 59% reduced risk for DFE from food sources (OR = 0.41; 95% CI = 0.26-0.65) and a 35% reduced risk for DFE from all sources (OR = 0.65; 95% CI = 0.42-1.00). In the joint-effects analyses using never smokers with high folate intake as the reference group (OR = 1.0), heavy smokers with low food folate intake had a 2.31-fold (95% CI = 1.11-4.82) increased risk, whereas heavy smokers with high folate intake had a reduced OR of 1.31 (95% CI = 0.53-3.26). Although the ORs were not statistically significant, light smokers and high folate intake exhibited a protective effect (OR = 0.62; 95% CI = 0.20-1.94), whereas an increased risk was observed for light smoking and low folate intake (OR = 1.41; 95% CI = 0.57-3.45). These patterns were consistent for the joint effects of smoking and DFE from food sources and DFE from all sources. In summary, high intake of dietary folate was associated with an overall decrease in bladder cancer risk. These data may have important implications for cancer prevention; however, large, hypothesis-driven, population-based clinical trials will be required to confirm these findings.

Preliminary Report of a Multicentric Study on Environmental Risk Factors in Ta-T1 Transitional Cell Carcinoma of the Bladder

OBJECTIVE

The distribution of potential environmental risk factors among patients affected by superficial transitional cell carcinoma of the bladder (TCCB) has been analyzed.

METHODS

Patients affected by superficial TCCB underwent TUR and early intravesical chemotherapy. Detailed data about age, sex, residence, employment, active and passive cigarette smoking, water resource and hair dye use were centralized. Analysis has been conducted on 474 patients affected by Ta-T1 G1-2 TCCB at medium risk for recurrence. Patients with primary single Ta G1-2, Tis or T1G3 tumors were excluded from the present analysis.

RESULTS

Over 80% of the patients lived in urban areas, 22% were employed in industries presumed at risk for bladder cancer, 8% used hair dye and 75% were smokers. Bottled water was the only water resource in 42% of the patients. Employment in industry at risk (p = 0.01) and cigarette smoking (p = 0.04) resulted in being statistically related to tumor multiplicity. Moreover, the period of cigarette smoking was significantly longer in patients with recurrent tumors (p = 0.026). The municipal water supply represented the main water source in never-smokers (p = 0.01) rather than in smokers and in patients harboring T1 rather than Ta tumors (p = 0.03).

CONCLUSIONS

Employment in industry at risk and cigarette smoking resulted in being related to tumor multiplicity. The length of exposure to cigarette smoking was related to the natural history of the tumor. A drinkable water source emerged as a risk factor in absence of cigarette smoking.

Trends in cancer mortality in Switzerland, 1980-2001

Trends in cancer mortality in Switzerland were analysed over the period 1980-2001, on the basis of the World Health Organization database. Appropriately developed correction factors were utilized for the period before 1995, to allow for spurious trends introduced by the change between the 8th and the 10th revisions of the ICD. Steady declines in cancer mortality were observed, particularly from the mid-1980s onwards. Over the last decade, the fall in overall age-standardized (world standard) cancer mortality was 11.1% in men (from 158.1 in 1990-1991 to 140.6/100,000 in 2000-2001) and 7.6% in women (from 91.6 to 84.7/100,000), and the decline was larger in truncated rates from 35 to 64 years (-18.0 and -9.7%). In men, all major tobacco and alcohol neoplasms have declined until the late 1990s but have levelled off over the last few years, reflecting recent trends in alcohol and tobacco consumption. The fall in male lung cancer mortality was 20% over the last decade (from 42.9 to 34.3/100,000). In contrast, lung cancer mortality in women has steadily increased by 38% between 1981 and 1991 and by 47% between 1991 and 2001, to reach 10.7/100,000 at all ages and 18.3 at age 35 to 64, due to increased prevalence of smoking in subsequent generations of Swiss women. Other sites showing substantial declines include stomach and colorectum in both sexes, (cervix) uteri and breast in women. Likewise, prostate cancer showed modest favourable trends after 1995. Steady declines were observed for leukaemias, Hodgkin's disease and testicular cancer, namely, the neoplasms most influenced by therapeutic improvements, while trends in lymphomas and myeloma showed no clear pattern.

Bladder Cancer Risk in Painters: a Review of the Epidemiological Evidence, 1989–2004*

Epidemiological studies on the potential association between painting and the risk of bladder cancer published after the Monograph of the International Agency for Research on Cancer N. 47 of 1989 have been systematically reviewed. These included four cohort studies on the incidence of bladder cancer among painters, with a pooled relative risk (RR) of 1.10 (95% confidence interval, CI, 1.03-1.18), based on 893 cases observed. The corresponding summary RR from four cohort studies on mortality was 1.23 (95% CI 1.11-1.37), based on 370 deaths. The pooled RR from 14 case-control studies and a pooled-analysis of other 11 case-control studies was 1.35 (95% CI 1.19-1.53), based on 465 cases exposed. Overall, the RR from all epidemiological studies was 1.17 (95% 1.11-1.27). Thus, recent epidemiological evidence indicates a moderate excess risk for bladder cancer in painters. Some studies, however, suggested that any such risk would have been greater for exposures in the distant past. Open issues for interpretation include residual confounding by social class and tobacco smoking, and understanding the time-risk relation. In particular, the potential residual risk related to exposure over the last two to three decades remains to be defined.

Dietary habits and risk of urothelial cancer death in a large-scale cohort study (JACC Study) in Japan

In the present study, the associations of dietary habits with the risk of urothelial cancer death were evaluated taking into consideration sex, age, and smoking habits. The Japan Collaborative Cohort Study was established in 1988-1990 and consisted of 47,997 men and 66,520 women observed until the end of 1999. A self-administered food-frequency questionnaire was used as a baseline survey. Hazard ratios for dietary factors were calculated by Cox's proportional hazards model. During the observation period, 63 men and 25 women died of urothelial cancer. Increasing age, male gender, and history of smoking were all significantly associated with increased risk of urothelial cancer death. A high intake of milk and fruits other than oranges reduced the risk significantly and dose dependently, in particular among subjects with smoking history. However, consumption of butter and yogurt had no associations with the risk. Intakes of cabbage, lettuce, green leafy vegetables, carrots, squash, tomatoes, and oranges were not significantly associated with the risk. It was suggested that urothelial cancer death could be potentially preventable by smoking cessation and regular intake of milk and fruit.

Trends in cancer mortality in the Americas, 1970-2000

BACKGROUND

Data and statistics on cancer mortality over the last decades are available for most developed countries, while they are more difficult to obtain, in a standardized and comparable format, for countries of Latin America.

PATIENTS AND METHODS

Age standardized (world population) mortality rates around the year 2000, derived from the WHO database, are presented for 14 selected cancers and total cancer in 10 countries of Latin America, plus, for comparative purposes, Canada and the USA. Trends in mortality are also given over the period 1970-2000.

RESULTS

In 2000, the highest total cancer mortality for males was observed in Argentina and Chile, with rates comparable to those of Canada and the USA, i.e. about 155/100,000. For women, Chile and Cuba had the highest rates in Latin America (114 and 103/100,000, respectively), again comparable to those of North America (around 105/100,000). These reflect the comparatively high mortality from cancer of the stomach (for Chile), lung and intestines (for Argentina) in men, and of stomach and uterus (for Chile), intestines and lung (for Cuba) in women. Colombia, Ecuador and Mexico had the lowest total cancer mortality for men, due to low mortality from stomach, colorectal and lung cancer. For women, the lowest rates were in Brazil and Puerto Rico, reflecting their low stomach and cervical cancer rates. In Argentina, Chile, Colombia, Costa Rica and Venezuela cancer mortality rates tended to decline, particularly in men. Rates were stable in Ecuador and Puerto Rico, and were increasing in Mexico and Cuba.

CONCLUSIONS

Mortality from some common cancers (including colorectal and lung) is still low in Latin America compared with Canada and the USA, and decreasing trends have been observed in the last decades for some cancer sites (including stomach, uterus, lung and other tobacco-related cancers) in several countries. However, mortality from female lung and breast cancers has been increasing in most countries of Latin America, and several countries still show an extremely elevated mortality from cancer of the cervix. Selected neoplasms amenable to treatment, including testis and leukemias, also show unsatisfactory trends in Latin America.

Dietary Habits and Risk of Urothelial Cancer Incidence in the JACC Study

BACKGROUND: The relationships between dietary habits and urothelial cancer have been discussed in many epidemiologic studies, however, they have not been sufficiently elucidated. In the present study, the associations of dietary habits with the risk of urothelial cancer incidence were evaluated taking into consideration sex, age, and smoking habits.

METHODS: The Japan Collaborative Cohort Study (JACC Study) was planned in the late 1980s as a large-scale cohort study surveying people comprehensively and detailing their lifestyles, and the study subjects were followed up until the end of 1997. Among the total of 110,792 participants, 26,464 men and 38,720 women were in areas where incident cases with cancer were identified. During the observation period, 95 men and 28 women suffered from urothelial cancer. Hazard ratios for dietary factors were calculated by Cox’s proportional hazards model.

RESULTS: Increasing age, male gender, and smoking history were all significantly associated with the risk of urothelial cancer. High consumption of pork was significantly associated with the risk. In contrast, high intakes of milk and fresh fish were significantly inversely associated with the risk. High intakes of Chinese cabbage and fruits were also significantly inversely associated with the risk of urothelial cancer.

CONCLUSIONS: It is suggested that high intakes of milk, fresh fish, Chinese cabbage, and fruits have preventive effects against urothelial cancer.

Trends in cancer mortality in Mexico, 1970–1999

BACKGROUND

Few data on cancer mortality have been published for Mexico over the last few decades. It is therefore of interest to conduct a systematic and updated analysis of cancer mortality in this country.

PATIENTS AND METHODS

Age-standardised (world population) mortality rates, at all ages and truncated at age 35-64 years, from major cancers and all cancers combined were computed on the basis of certified deaths derived from the World Health Organization database for the period 1970-99.

RESULTS

Mortality rates for all neoplasms showed an upward trend in men of all ages (from 58.2/100,000 in 1970-74 to 87.1/100,000 in 1995-99) and in middle-aged men (from 76.1 to 93.7/100,000, respectively). This reflects the rise until the early 1990s in lung cancer mortality (from 8.1/100,000 in 1970-74 to 15.6/100,000 in 1995-99) and prostate cancer (from 5.5 to 12.2/100,000, respectively). In women, overall mortality rates showed an increase between the early 1970s (75.4/100,000) and the late 1990s (82.3/100,000). Total cancer mortality rates remained low, however, compared with other American countries (e.g. 153.3/100,000 men and 108.6/100,000 women in 1999 in the United States). Truncated rates were stable (126.5/100,000 in 1970-74 and 125.8/100,000 in 1995-99), although they were much higher than overall rates, reflecting exceedingly high rates for uterine (mostly cervical) cancer mortality in middle-aged women (29.5/100,000 in 1995-99).

CONCLUSIONS

Total cancer mortality in Mexico has remained comparably low on a worldwide scale, and the upward trends in mortality rates for lung and other tobacco-related neoplasms have tended to level off over the last decade. However, steady rises have been observed for other major cancers, including prostate and breast. Cervical cancer remains a major health problem in women.

Cigarette smoking and the risk of bladder cancer in men and women

Although cigarette smoking is a principal risk factor for bladder cancer in both men and women, few studies have statistically evaluated whether gender modifies the effect of smoking on bladder cancer risk. We initiated the present case-control study at Roswell Park Cancer Institute in Buffalo, New York, U.S., to provide further data on this important issue. We observed similar risk estimates for men and women with comparable smoking exposures, but did not observe a statistically significant interaction between gender and lifetime smoking exposure. We conclude that cigarette smoking is a major risk factor for bladder cancer in both sexes, but that gender does not modify the effect of smoking on bladder cancer risk.

Cigarette Smoking and the Risk of Bladder Cancer in Men and Women

Although cigarette smoking is a principal risk factor for bladder cancer in both men and women, few studies have statistically evaluated whether gender modifies the effect of smoking on bladder cancer risk. We initiated the present case-control study at Roswell Park Cancer Institute in Buffalo, New York, U.S., to provide further data on this important issue. We observed similar risk estimates for men and women with comparable smoking exposures, but did not observe a statistically significant interaction between gender and lifetime smoking exposure. We conclude that cigarette smoking is a major risk factor for bladder cancer in both sexes, but that gender does not modify the effect of smoking on bladder cancer risk.

Cancer mortality in Europe, 1995-1999, and an overview of trends since 1960

Mortality data, abstracted from the World Health Organization database, are presented in tabular form for 26 cancer sites or groups of sites, plus total cancer mortality, in 36 European countries during the period 1995-1999. Trends in mortality are also given in graphic form for 23 major countries plus the European Union as a whole over the period 1960-1999. In the European Union, total cancer mortality declined by 7% for both sexes over the last 5 years considered. The fall since the late 1980s was 10% in both sexes, corresponding to the avoidance of over 90000 deaths per year, as compared to the rates of the late 1980s. For the first time, over the last few years, some leveling of mortality was reported also in the Russian Federation, the Czech Republic, Poland, Hungary and other Eastern European countries, although cancer rates in those areas remain exceedingly high. The overall favorable pattern of cancer mortality over recent years is largely driven by the decline of tobacco-related cancer mortality in men. However, important components of the trends are also the persistence of substantial falls in gastric cancer, mainly in Russia and Eastern Europe, the recent decline in intestinal cancer in both sexes and of breast cancer in women, together with the long-term falls in uterine (cervical) cancer, leukemias, Hodgkin's disease and other neoplasms amenable to advancements in diagnosis and treatment. Female lung cancer mortality has been declining in the Russian Federation, but is still rising in other areas of the continent. Thus, urgent intervention is needed to bring under control the tobacco-related lung cancer epidemic in European women before it reaches the high level observed in North America. Supplementary material for this article can be found on the International Journal of Cancer website at http://www.interscience.wiley.com/jpages/0020-7136/suppmat/index.html

Lung cancer risk after exposure to polycyclic aromatic hydrocarbons: a review and meta-analysis

Typical polycyclic aromatic hydrocarbon mixtures are established lung carcinogens, but the quantitative exposure-response relationship is less clear. To clarify this relationship we conducted a review and meta-analysis of published reports of occupational epidemiologic studies. Thirty-nine cohorts were included. The average estimated unit relative risk (URR) at 100 Mu g/m (superscript)3(/superscript) years benzo[a]pyrene was 1.20 [95% confidence interval (CI), 1.11-1.29] and was not sensitive to particular studies or analytic methods. However, the URR varied by industry. The estimated means in coke ovens, gasworks, and aluminum production works were similar (1.15-1.17). Average URRs in other industries were higher but imprecisely estimated, with those for asphalt (17.5; CI, 4.21-72.78) and chimney sweeps (16.2; CI, 1.64-160.7) significantly higher than the three above. There was no statistically significant variation of URRs within industry or in relation to study design (including whether adjusted for smoking), or source of exposure information. Limited information on total dust exposure did not suggest that dust exposure was an important confounder or modified the effect. These results provide a more secure basis for risk assessment than was previously available.

Primary care update on kidney and bladder cancer: a urologic perspective

The past decade has witnessed many substantive changes in the approach to the diagnosis and treatment of both kidney and bladder cancer. In part, this is based on changes in the understanding of their carcinogenesis and pathogenesis, an appreciation of new concepts in their classification, and the incorporation of new technologies that have emerged. This article reviews advances and updates changes that have been made in the understanding of and approaches to these malignancies from the perspective of their urologic assessment and management while in the context of primary care issues.

Fluid intake and risk of bladder and other cancers

There are appreciable differences in total fluid intake at the individual and population level, and substantial difficulties in obtaining valid measures of fluid intake. Epidemiological studies have examined the association between fluid intake and different types of cancer. For bladder cancer, fluid consumption has been associated with a moderate increase of risk in some studies, including a multicentric case-control study from the United States, based on about 3000 cases, with a decrease in others, including the Health Professional Follow-up study, or with no material association. The evidence, therefore, is far from consistent. Sources and components of fluids were also different across different types studies. From a biological point of view, a decreased fluid intake could result in a greater concentration of carcinogens in the urine or in a prolonged time of contact with the bladder mucosa because of less frequent micturition. Carcinogenic or anticarcinogenic components of various beverages excreted in the urine may also play a role in the process. It has been suggested that fluid consumption has a favorable effect on colorectal cancer risk. Fluid intake may reduce colon cancer risk by decreasing bowel transit time and reducing mucosal contact with carcinogens. Low fluid intake may also compromise cellular concentration, affect enzyme activity in metabolic regulation, and inhibit carcinogen removal. However, epidemiological data are inadequate for evaluation. Data are sparse and inconsistent for other neoplasms, including breast cancer. The fluid constituent of foods, confounding, interactions and possible influences of specific types of beverages should be investigated further. In conclusion therefore the association between total fluid intake and cancer risk remains still open to debate.

The association between smoking, beverage consumption, diet and bladder cancer: a systematic literature review

In this paper the association between smoking history, beverage consumption, diet and bladder cancer incidence is systematically reviewed. A rating system has been used to summarise the level of scientific evidence (i.e. convincing, probable, possible, and no evidence) and the level of association (i.e. substantially increased, (RR> or =2.5), moderately increased (1.5< or =RR<2.5), slightly increased (1.2< or =RR<1.5), no association (0.8< or =RR<1.2), slightly decreased (0.7< or =RR<0.8), moderately decreased (0.4< or =RR<0.7), and substantially decreased (RR<0.4)). There is convincing evidence that cigarette smoking status, frequency and duration substantially increase the risk of bladder cancer. However, the evidence is not clear for other forms of smoking. A small increased risk for cigar, pipe, and environmental smoking is only possible. There is possible evidence that total fluid intake is not associated with bladder cancer. Although there is convincing evidence for a positive association between alcohol consumption and bladder cancer risk in men, the risk is small and not clinically relevant. Coffee and tea consumption are probably not associated with bladder cancer. The authors conclude that total fruit consumption is probably associated with a small decrease in risk. There is probably no association between total vegetable intake, vitamin A intake, vitamin C intake and bladder cancer and a possibly moderate inverse association with vitamin E intake. Folate is possibly not associated with bladder cancer. There probably is a moderate inverse association between selenium intake and bladder cancer risk.

Neoadjuvant chemotherapy plus cystectomy compared with cystectomy alone for locally advanced bladder cancer

BACKGROUND

Despite aggressive local therapy, patients with locally advanced bladder cancer are at significant risk for metastases. We evaluated the ability of neoadjuvant chemotherapy to improve the outcome in patients with locally advanced bladder cancer who were treated with radical cystectomy.

METHODS

Patients were enrolled if they had muscle-invasive bladder cancer (stage T2 to T4a) and were to be treated with radical cystectomy. They were stratified according to age (less than 65 years vs. 65 years or older) and stage (superficial muscle invasion vs. more extensive disease) and were randomly assigned to radical cystectomy alone or three cycles of methotrexate, vinblastine, doxorubicin, and cisplatin followed by radical cystectomy.

RESULTS

We enrolled 317 patients over an 11-year period, 10 of whom were found to be ineligible; thus, 154 were assigned to receive surgery alone and 153 to receive combination therapy. According to an intention-to-treat analysis, the median survival among patients assigned to surgery alone was 46 months, as compared with 77 months among patients assigned to combination therapy (P=0.06 by a two-sided stratified log-rank test). In both groups, improved survival was associated with the absence of residual cancer in the cystectomy specimen. Significantly more patients in the combination-therapy group had no residual disease than patients in the cystectomy group (38 percent vs. 15 percent, P<0.001).

CONCLUSIONS

As compared with radical cystectomy alone, the use of neoadjuvant methotrexate, vinblastine, doxorubicin, and cisplatin followed by radical cystectomy increases the likelihood of eliminating residual cancer in the cystectomy specimen and is associated with improved survival among patients with locally advanced bladder cancer.

Hormone replacement therapy and cancer risk: a systematic analysis from a network of case-control studies

To provide comprehensive and quantitative information on the benefits and risks of hormone replacement therapy (HRT) on several cancer sites, we systematically examined the relation between HRT use and the risk of various cancers in women aged 45-79 by using data from a framework of case-control studies conducted in Italy between 1983 and 1999. The overall data set included the following incident, histologically confirmed neoplasms: oral cavity, pharynx, larynx and esophagus (n = 253), stomach (n = 258), colon (n = 886), rectum (n = 488), liver (n = 105), gallbladder (n = 31), pancreas (n = 122), breast (n = 4,713), endometrium (n = 704), ovary (n = 1,614), urinary bladder (n = 106), kidney (n = 102), thyroid (n = 65), Hodgkin's disease (n = 26), non-Hodgkin's lymphomas (n = 145), multiple myeloma (n = 65) and sarcomas (n = 78). The control group comprised 6,976 women aged 45-79 years, admitted for a wide spectrum of acute, nonneoplastic conditions. Odds ratios (OR) and the corresponding 95% confidence intervals (CI) for use of HRT were derived from multiple logistic regression equations. There was an inverse association between ever use of HRT and colon (OR = 0.7), rectum (OR = 0.5) and liver cancer (OR = 0.2), with a consistent pattern of protection for duration of use. An excess risk was found for gallbladder (OR = 3.2), breast (OR = 1.1), endometrial (OR = 3.0) and urinary bladder cancer (OR = 2.0). These data from a southern European population add some useful information on the risk-benefit assessment of HRT among postmenopausal women.

CYP2E1 and NQO1 genotypes, smoking and bladder cancer

BACKGROUND

Cytochrome P450 2E1 (CYP2E1) and NAD(P)H:quinone oxidoreductase (NQO1) catalyze the activation of some environmental procarcinogens present in tobacco smoke (i.e. nitrosoamines and heterocyclic amines). We conducted a hospital based case-control study to evaluate the potential association between genetic polymorphisms of CYP2E1 (C1019T in the 5' flanking region) and NQO1 (C609T in exon 6) and bladder cancer risk in Asian population.

METHODS

The study population was comprised of 218 histologically confirmed prevalent bladder cancer cases and 199 controls without cancer or systemic illness. PCR-restriction fragment length polymorphism based methods were used for the genotyping analyses and unconditional logistic regression model for the statistical evaluations.

RESULTS

The risk of bladder cancer increased with the amount of smoking (P for trend < 0.01). The frequency of CYP2E1 c1/c1 genotype was significantly higher in bladder cancer patients (57.9%) than in the controls (47.9%) (OR = 1.8, 95% CI = 1.1-2.9). Similarly, the NQO1 C/C genotypes were significantly more prevalent in the patients (45.8%) than in the controls (37.6%) (OR = 1.6, 95% CI = 1.0-2.7). The risk for bladder cancer increased with the number of the putative risk genotypes (P for trend = 0.03); the most remarkable risk was observed for heavy smokers with both CYP2E1 c1/c1 and NQO1 C/C genotypes (OR = 13.8, 95% CI = 3.9-48.6) when compared to non/light smokers with other genotypes.

CONCLUSION

Our findings suggest that CYP2E1 and NQO1 genotypes may play an important role in development of smoking related bladder cancer among Korean men.

Mortality from major cancer sites in the European Union, 1955-1998

After long-term rises, over the last decade age-standardised mortality from most common cancer sites has fallen in the European Union (EU). For males, the fall was 11% for lung and intestines, 12% for bladder, 6% for oral cavity and pharynx, and 5% for oesophagus. For females, the fall was 7% for breast and 21% for intestines. There were also persisting declines in stomach cancer (30% in both sexes), uterus (mainly cervix, -26%) and leukaemias (-10%). Mortality rates for other common neoplasms, including pancreas for both sexes, prostate and ovary, tended to stabilise. The only unfavourable trends were observed for female lung cancer (+15%). Lung cancer rates in women from the EU are approximately one-third of those in the USA, and 50% lower than breast cancer rates in the EU. Lung cancer rates in European women have also tended to stabilise below the age of 75 years. Thus, effective interventions on tobacco control could, in principle, avoid a major lung cancer epidemic in European women.

Induction of transitional cell hyperplasia in the urinary bladder and aberrant crypt foci in the colon of rats treated with individual and a mixture of drinking water disinfection by-products

Cancer of the urinary bladder and colon are significant human health concerns. Epidemiological studies have suggested a correlation between these cancers and the chronic consumption of chlorinated surface water containing disinfection by-products (DBPs). The present study was designed to determine if exposure to DBPs would cause preneoplastic or neoplastic lesions in the urinary bladder and colon of rats, and what effect a mixture of DBPs would have on these lesions. Male and female Eker rats were treated via drinking water with low and high concentrations of potassium bromate, 3-chloro-4-(dichloromethyl)-5-hydroxy-2(5H)-furanone (MX), chloroform, or bromodichloromethane individually or in a mixture for 10 months. The urinary bladders and colons were examined for the presence of preneoplastic lesions. Cell proliferation in the urothelium was examined using immunohistochemical staining for bromodeoxyuridine. Aberrant crypt foci (ACF), as well as the number of individual crypts in each ACF, were identified and counted microscopically after staining with 0.2% methylene blue. Colon crypt cell proliferation and mitotic index were determined using immunohistochemical staining for proliferating cell nuclear antigen. Labeling indexes for the urinary bladder and colon were calculated based on the percentage of positively labeled cells. Treatment with the high dose of MX caused transitional epithelial hyperplasia and cell proliferation in the rat urinary bladder, and this effect was diminished in the high dose mixture animals. Treatment with 4 individual DBPs, as well as a mixture of them, caused the development of ACF, the putative preneoplastic lesion of colon cancer.

Bladder cancer

Bladder cancer is a common and chemotherapy-responsive tumor, related to tobacco smoking, environmental arsenic exposure, industrial dye exposure, and parasitic schistosomiasis exposure. Both reduction of carcinogen exposure and chemoprevention, possibly with cyclooxygenase 2 inhibitors, should reduce the incidence. The search for the ideal screening and monitoring test continues with some promising new candidates, including survivin. Although 10-year survival can be achieved in 87% of early-stage patients with muscle-invasive disease rendered T(0) and 57% of those rendered T(1) at second look after transurethral resection bladder tumor, most still require radical cystectomy. Continued improvements in surgical techniques permit gains in quality of life after the procedure. Ten-year survival can still be achieved with cystectomy in the face of grossly positive lymph nodes in 32% of T(2) and 10% of T(3) patients. A recent meta-analysis indicates that preoperative irradiation is unlikely to be beneficial, but definitive chemoradiation can produce significant 5-year survival rates in nonoperative candidates and those desiring bladder preservation. The Intergroup now has preliminary data from a Southwest Oncology Group-based trial showing a significant benefit for neoadjuvant methotrexate, vinblastine, doxorubicin, and cisplatin. The regimen of gemcitabine and cisplatin is equally efficacious with less toxicity than methotrexate, vinblastine, doxorubicin, and cisplatin. It has been adopted as the standard arm in a phase III trial for advanced bladder cancer, comparing it with the triplet of gemcitabine, paclitaxel, and cisplatin. Other active agents in bladder cancer include ifosfamide, carboplatin, docetaxel, and vinorelbine, and various doublets of these agents are being tested in phase II trials, with promising results.

Combined effect of glutathione S-transferase M1 and T1 genotypes on bladder cancer risk

To evaluate the association between genetic polymorphism of GSTM1, GSTT1 and development of bladder cancer, a hospital-based case-control study was conducted in South Korea. The study population consisted of 232 histologically confirmed male bladder cancer cases and 165 male controls enrolled from urology departments with no previous history of cancer or systemic diseases in Seoul during 1997-1999. The GSTM1 null genotype was significantly associated with bladder cancer (OR: 1.6, 95% CI: 1.0-2.4), whereas the association observed for GSTT1 null genotype did not reach statistical significance (OR: 1.3, 95% CI: 0.9-2.0). There was a statistically significant multiple interaction between GSTM1 and GSTT1 genotype for risk of bladder cancer (P=0.04); the risk associated with the concurrent lack of both of the genes (OR: 2.2, 95% CI: 1.2-4.3) was greater than the product of risk in men with GSTM1 null/GSTT1 present (OR: 1.3, 95% CI: 0.7-2.5) or GSTM1 present/GSTT1 null (OR: 1.1, 95% CI: 0.6-2.2) genotype combinations.

c-Src-dependent activation of the epidermal growth factor receptor and mitogen-activated protein kinase pathway by arsenic. Role in carcinogenesis

Environmental or occupational exposure to arsenic is associated with a greatly increased risk of skin, urinary bladder, and respiratory tract cancers in arseniasis-endemic areas throughout the world. Arsenic shares many properties of tumor promoters by affecting specific cell signal transduction pathways responsible for cell proliferation. The activation of the epidermal growth factor receptor (EGFR)-extracellular signal-regulated protein kinase (ERK) pathway is important in mediating gene expression related to regulation of cellular growth. In the current studies, we demonstrate that arsenic activates EGFR and ERK in a human uroepithelial cell line. The EGFR phosphorylation by arsenic is ligand-independent and does not involve the major autophosphorylation site Tyr(1173). c-Src activity is also induced by arsenic and is a prerequisite for the EGFR and ERK activation. Consistent with these in vitro observations, exposure of mice to arsenic in drinking water, which has been found previously to be associated with AP-1 activation and epithelial proliferation, induces EGFR and ERK activation in the urinary bladder. This response is also accompanied with an increase in c-Src levels interacting with EGFR. These findings represent a potential pathway for mediating arsenic-induced phenotypic changes in the uroepithelium.